Hibernate lazy loading not work with many-to-one mapping



I have problem of permformance in my many-to-one mapping. When I debug the SQL query in log file the principal query it's ok, but after i have other query representing many-to-one object mapping.


Entity.hbm.xml :



<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://ift.tt/UNuKEd" >

<hibernate-mapping>
<class name="com.omb.database.mapping.MyEntity" table="MY_ENTITY">
<id name="id" type="java.lang.Integer">
<column name="ENTITY_ID"/>
<generator class="sequence">
<param name="sequence">SEQ_MY_ENTITY</param>
</generator>
</id>

<property name="prop1" type="string" column="PROP1" />
<many-to-one name="object1" column="OBJECT1_ID" class="com.omb.database.mapping.Object1" />
<many-to-one name="object2" column="OBJECT2_ID" class="com.omb.database.mapping.Object2" />

</class>
</hibernate-mapping>


Object1.hbm.xml :



<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://ift.tt/UNuKEd" >

<hibernate-mapping default-lazy="true">

<class name="com.omb.database.mapping.Object1" table="TABLE_OBJECT_1">
<id name="id" type="java.lang.Integer" column="OBJECT1_ID" />
<property name="label" type="string" column="LABEL_OBJECT_1" length="15" />
</class>

</hibernate-mapping>


Object2.hbm.xml :



<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://ift.tt/UNuKEd" >

<hibernate-mapping default-lazy="true">

<class name="com.omb.database.mapping.Object2" table="TABLE_OBJECT_2">
<id name="id" type="java.lang.Integer" column="OBJECT2_ID" />
<property name="label" type="string" column="LABEL_OBJECT_2" length="15" />
</class>

</hibernate-mapping>


Query HBM :



public List<Entity> findByObject1Id(Integer object1Id) throws DataAccesException {

List<Entity> results = null;
try {
Query query = this.getSession().createQuery(
"from Entity ent where ent.object1.id = :object1Id");
query.setParameter("object1Id", object1Id);
results = query.list();
} catch (HibernateException hbe) {
throw new DataAccesException(hbe);
}

return results;
}


in pom.xml



<!-- Hibernate 3 -->
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate</artifactId>
<version>3.2.6.ga</version>
<exclusions>
<exclusion>
<groupId>javax.transaction</groupId>
<artifactId>jta</artifactId>
</exclusion>
<exclusion>
<groupId>net.sf.ehcache</groupId>
<artifactId>ehcache</artifactId>
</exclusion>
<exclusion>
<groupId>asm</groupId>
<artifactId>asm-attrs</artifactId>
</exclusion>
</exclusions>
</dependency>

No comments:

Post a Comment